The invention relates to a process for depositing fluids in a solids flow of a spouted bed apparatus and an associated apparatus.
From DE 31 17 892 A1, a spouted bed apparatus for producing granulates is known, for which a fluid is introduced into the solids flow of the spouted bed granulator. The spouted bed apparatus has a round cross section, whose lower part is formed with a conical taper. A gas channel, where a nozzle for injecting the fluid is arranged, opens into the central conical part of the spouted bed granulator. An appropriate gas is fed through the gas channel for maintaining the spouted bed. The centrally fed gas entrains the fluid introduced by the nozzles and a portion of the material located in the spouted bed granulator, wherein a stream channel is produced in which the material particles are wetted with the fluid. The sprayed material is fed back to the stream channel over the conical base, so that particle circulation is generated. After achieving an adequate granulate size, the granulates are discharged from the spouted bed granulator.
A disadvantage for this type of spouted bed granulator is that the supply of gas for generating the spouted bed and the introduced fluid is supplied at a common location in the lower part of the spouted bed granulator. A uniform wetting of all material particles to be treated with fluid is hard or impossible to realize. Some material particles are sprayed with too much and others with too little fluid, so that an end product with equal grain size and equal material structure cannot be realized. In addition, these systems are only suitable for granulation at low material throughputs. For greater throughputs, problems appear in terms of generating and maintaining the spouted bed.
Previously known from the publication DE 100 04 939 C1 is a spouted bed apparatus for fluidization and thermal treatment of essentially arbitrarily shaped materials with different particle dimensions as well as particle masses. The spouted bed apparatus for batch or continuous process control consists of an inlet air chamber arranged in the lower region of the spouted bed apparatus, into which the fluidizing means, such as, especially air, is supplied. The fluidizing means is fed to the fluidization region of the spouted bed apparatus by means of a controllable gas flow device arranged between the inlet air chamber and the fluidization region. The fluidization region is formed by the gas flow device arranged in the lower region, as well as by a stream inlet wall, a stream return flow wall lying opposite the stream inlet wall, and also the side walls. The stream inlet wall and the stream return flow wall are inclined relative to the vertical, so that they form a cone. Therefore, an expanded cross section of the spouted bed apparatus is formed above the stream inlet wall and the stream return flow wall. This expanded section is used as an expansion region for the fluidizing means and is provided with an outlet for the exhaust air. The spouted bed apparatus can be one-sided or two-sided, i.e., it can be formed with a double cone. Through the arrangement of the stream inlet wall and the stream return flow wall as well as through the supply of fluidizing means through the gas flow device, a type of solids rotation is produced in the fluidization region, in which a corresponding material treatment is performed.
An introduction of fluids into the solids flow is not provided with this type of stream apparatus.